Author(s):
Coelho, Francisco J. R. C. 
; Rocha, Rui J. M. ; Pires, Ana C. C. ; Ladeiro, Bruno ; Castanheira, José M. ; Costa, Rodrigo ; Almeida, Adelaide ; Cunha, Ângela ; Lillebo, Ana I. ; Ribeiro, R. ; Pereira, Ruth ; Lopes, Isabel ; Marques, Catarina ; Moreira-Santos, Matilde ; Calado, Ricardo ; Cleary, Daniel F. R. ; Gomes, Newton C. M.
Date: 2013
Persistent ID: http://hdl.handle.net/10316/25582
Origin: Estudo Geral - Universidade de Coimbra
Subject(s): benthic communities; climate change; marine sediments; microbial ecology; microcosm; pyrosequencing
Description
An experimental life support system (ELSS) was constructed to study the interactive effects of multiple stressors on
coastal and estuarine benthic communities, specifically perturbations driven by global climate change and anthropogenic
environmental contamination. The ELSS allows researchers to control salinity, pH, temperature, ultraviolet
radiation (UVR), tidal rhythms and exposure to selected contaminants. Unlike most microcosms previously
described, our system enables true independent replication (including randomization). In addition to this, it can be
assembled using commercially available materials and equipment, thereby facilitating the replication of identical
experimental setups in different geographical locations. Here, we validate the reproducibility and environmental
quality of the system by comparing chemical and biological parameters recorded in our ELSS with those prevalent in
the natural environment. Water, sediment microbial community and ragworm (the polychaete Hediste diversicolor)
samples were obtained from four microcosms after 57 days of operation. In general, average concentrations of dissolved
inorganic nutrients (NO3
; NH4
+ and PO4
3) in the water column of the ELSS experimental control units were
within the range of concentrations recorded in the natural environment. While some shifts in bacterial community
composition were observed between in situ and ELSS sediment samples, the relative abundance of most metabolically
active bacterial taxa appeared to be stable. In addition, ELSS operation did not significantly affect survival, oxidative
stress and neurological biomarkers of the model organism Hediste diversicolor. The validation data indicate that this
system can be used to assess independent or interactive effects of climate change and environmental contamination
on benthic communities. Researchers will be able to simulate the effects of these stressors on processes driven by
microbial communities, sediment and seawater chemistry and to evaluate potential consequences to sediment toxicity
using model organisms such as Hediste diversicolor. This study was supported by the Centre for Environmental
and Marine Studies (CESAM), the Foundation for Science and
Technology (FCT, Portugal) PTDC/AAC-CLI/107916/2008
(http://alfa.fct.mctes.pt) and the European Regional Development
Fund (ERDF) through COMPETE-(FCOMP-01-0124-
FEDER-008657). Francisco J.R.C. Coelho and Rui J. M. Rocha
were supported by a PhD scholarship (SFRH/BD/46322/2008
and SFRH/BD/46675/2008, respectively) funded by FCT
(QREN-POPH – Type 4.1 – Advanced Training, subsidized by
the European Social Fund and national funds MCTES). We
thank Jos e Ferreira from EpArq, Aveiro University for graphical
design of the ELSS.
